Preparation:

Combine buttermilk and oil. Whisk whole-wheat flour, all-purpose flour, sugar, baking powder, baking soda and salt in a large bowl. Using your fingertips or 2 knives, cut butter into the dry ingredients until crumbly. Make a well in the center and gradually pour in the buttermilk mixture, stirring with a fork until just combined.

3

Transfer the dough to a floured surface and sprinkle with a little flour. Lightly knead the dough 8 times, then pat or roll out to an even 3/4-inch thickness. Cut into 2-inch rounds and transfer to the prepared baking sheet. Gather any scraps of dough and cut more rounds. Brush the tops with milk.

4

Bake the biscuits for 12 to 16 minutes, or until golden brown. Transfer to a wire rack and let cool slightly before serving.